The general aim of the research is to study the cellular mechanisms involved in the detection and analysis of light stimuli by the vertebrate retina. At present, before proceeding to the interactions between higher order retinal neurons, it seems appropriate to study further the generation and transmission of neural signals at the level of the receptors. When these studies are completed, interactions between higher order retinal neurons will be approached, with the long range goal of obtaining a reasonably complete picture of the way in which the cells in the retina accomplish the tasks of signal detection and analysis.